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Get all slice permutations

I was wondering if there is a way to find all permutations of a slice filled with characters in Go?

In Python, you can use itertools.productwith a list or characters or integers, and you can get all possible permutations.

I looked to see if there was a package, and I can not find it. Any help would be appreciated.

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3 answers

Permutations of something that implements sort.Interface: Permutation {First, Next}

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Here is the implementation of the permutation function that I wrote ...

https://github.com/itcraftsman/GoPermutation

func permutate(slice [][]int) (permutations [][][]int){
    f := fac(len(slice))
    for i := 0; i < len(slice); i++ {
        elem, s := splice(slice, i)
        pos := 0
        for count := 0; count < (f / len(slice)); count++{
            if pos == (len(s) -1) {
                pos = 0
            }
            s = swap(s, pos, pos +1)
            permutation := make([][]int, len(slice))
            permutation = s
            permutation = append(permutation, elem)
            permutations = append(permutations, permutation)
            pos++
        } 
    } 
    return
}

, , 2D-

0

Not sure if this is the answer to your question, but this is a simple recursive implementation to find the result below.

package main

import "fmt"

func main() {
    values := [][]int{}

    // These are the first two rows.
    row1 := []int{1, 2, 3}
    row2 := []int{4, 5, 6}
    row3 := []int{7, 8, 9}

    // Append each row to the two-dimensional slice.
    values = append(values, row1)
    values = append(values, row2)
    values = append(values, row3)


    fmt.Println(getPermutation(values))
}

func getPermutation(vids [][]int) [][]int {
    toRet := [][]int{}

    if len(vids) == 0 {
      return toRet
    }

    if len(vids) == 1 {
        for _, vid := range vids[0] {
            toRet = append(toRet, []int{vid})
        }
        return toRet
    }

    t := getPermutation(vids[1:])
    for _, vid := range vids[0] {
        for _, perm := range t {
            toRetAdd := append([]int{vid}, perm...)
            toRet = append(toRet, toRetAdd)
        }
    }

    return toRet
}

https://play.golang.org/p/f8wktrxkU0

The output above the snippet:

[[1 4 7] [1 4 8] [1 4 9] [1 5 7] [1 5 8] [1 5 9] [1 6 7] [1 6 8] [1 6 9] [2 4 7] [2 4 8] [2 4 9] [2 5 7] [2 5 8] [2 5 9] [2 6 7] [2 6 8] [2 6 9] [3 4 7] [3 4 8] [3 4 9] [3 5 7] [3 5 8] [3 5 9] [3 6 7] [3 6 8] [3 6 9]]
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